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arXiv · 0711.0033

The Metallicity Dependence of Wolf-Rayet Mass Loss

A. J. Onifer·A. Heger·J. Abdallah
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Abstract

We produce models of early WN, WC, and WO stars as a function of metallicity Z using an analytic CAK-type approach. At log(Z / Z_sun) >= -2 both WN and WC stars have the approximate dependence Mdot \propto Z^{0.5}. For a WN wind the mass-loss rate drops rapidly below log(Z / Z_sun) = -2, and no wind solution can be found for log(Z / Z_sun) < -3. For WC and WO winds the mass-loss rate plummets in the range -3 <= log(Z / Z_sun) <= -2 and tends to flatten due to the self-enrichment of C and O to around 10^{-8} M_sun yr^{-1} for log(Z / Z_sun) <= -4. No significant difference in Mdot was found for WC versus WO stars at low metallicity.

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A. J. Onifer, A. Heger, J. Abdallah. 2007-10-31. The Metallicity Dependence of Wolf-Rayet Mass Loss. https://arxiv.org/abs/0711.0033

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